User Manual of DS-6600 Audio/Video Encoder
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Appendix B Glossary
Dual Stream
Dual stream refers to that one channel of video stream can be divided into double independent output streams
through the video encoder. Shown as below:
Video Stream
Video Encoder
Main Stream
Sub Stream
The resolution, frame rate, bitrate and other parameters of the output stream are independently programmable. The
two streams generated may meet different application demands, e.g., one stream is used for HDD storage, and the
other for transmission via Internet.
Transparent Channel
The transparent channel indicates the channel used for transmitting data, and through which the data transmitted
receives no handling and thus retains no change. By remotely connecting the keyboard with the decoder, the
transparent channel can be established to realize control of dome or Pan/Tilt unit connected to remote encoder.
Resolution
The type of resolution can be divided into the display resolution, image resolution and pixel resolution.
The display resolution refers to the maximum display zone on the screen in certain display mode, measured in
horizontal and vertical pixel.
The image resolution describes the detail a digital image holds, measured in horizontal and vertical pixel as well.
In case the image resolution is higher than the display resolution, proportion of the image will not be displayed on
the screen.
The pixel resolution indicates the ratio of the pixel width and length. Different pixel width/length ratio will result
in different shape of image.
Generally the image resolution is applied to the digital surveillance:
PAL: QCIF (176*144), CIF(352*288), 2CIF(704*288), DCIF(528*384), 4CIF(704*576).
NTSC: QCIF (176*120), CIF(352*240), 2CIF(704*240), DCIF(528*320), 4CIF(704*480).
The display resolution is usually applied to VGA monitor:
640*480, 800*600, 1024*768, etc.
Streaming Server
The streaming server refers to a dedicated computer system or server which runs the corresponding streaming
media software to provide the delivery of data. It is generally applied to the delivery of the same massive data,
which may greatly reduce the load of the host as well as save internet resources.
